3 files changed, 10 insertions, 1 deletions
diff --git a/lib/sqlalchemy/sql/elements.py b/lib/sqlalchemy/sql/elements.py
index 56fca5dd8..c230802cc 100644
--- a/lib/sqlalchemy/sql/elements.py
+++ b/lib/sqlalchemy/sql/elements.py
@@ -1492,6 +1492,7 @@ class BooleanClauseList(ClauseList, ColumnElement):
     def _construct(cls, operator, continue_on, skip_on, *clauses, **kw):
         convert_clauses = []
 
+        clauses = util.coerce_generator_arg(clauses)
         for clause in clauses:
             clause = _literal_as_text(clause)
 
diff --git a/lib/sqlalchemy/util/__init__.py b/lib/sqlalchemy/util/__init__.py
index 77339e56a..fdf0c9dac 100644
--- a/lib/sqlalchemy/util/__init__.py
+++ b/lib/sqlalchemy/util/__init__.py
@@ -18,7 +18,8 @@ from ._collections import KeyedTuple, ImmutableContainer, immutabledict, \
     column_dict, ordered_column_set, populate_column_dict, unique_list, \
     UniqueAppender, PopulateDict, EMPTY_SET, to_list, to_set, \
     to_column_set, update_copy, flatten_iterator, \
-    LRUCache, ScopedRegistry, ThreadLocalRegistry, WeakSequence
+    LRUCache, ScopedRegistry, ThreadLocalRegistry, WeakSequence, \
+    coerce_generator_arg
 
 from .langhelpers import iterate_attributes, class_hierarchy, \
     portable_instancemethod, unbound_method_to_callable, \
diff --git a/lib/sqlalchemy/util/_collections.py b/lib/sqlalchemy/util/_collections.py
index a43115203..24a3c1767 100644
--- a/lib/sqlalchemy/util/_collections.py
+++ b/lib/sqlalchemy/util/_collections.py
@@ -6,10 +6,12 @@
 
 """Collection classes and helpers."""
 
+from __future__ import absolute_import
 import weakref
 import operator
 from .compat import threading, itertools_filterfalse
 from . import py2k
+import types
 
 EMPTY_SET = frozenset()
 
@@ -754,6 +756,11 @@ class UniqueAppender(object):
     def __iter__(self):
         return iter(self.data)
 
+def coerce_generator_arg(arg):
+    if len(arg) == 1 and isinstance(arg[0], types.GeneratorType):
+        return list(arg[0])
+    else:
+        return arg
 
 def to_list(x, default=None):
     if x is None: